In industry, there is often water contaminated with small amounts of solvent of the mentioned kind. There are no effective and economic aids in the art today, for high-degree purification of such water, the contaminated water therefore often being led off without purification, in contravention to current regulations.
In this connection it has indeed been proposed to purify water burdened with solvent by utilizing so-called strip columns. However, these are expensive and complicated, and it has been found impossible to reduce the solvent concentration to below 5 ppm thereby.